At least 23 sex offenders, most of them rapists and child molesters, became registered drug counselors in the past eight years.

A new report, released Monday by the Senate Office of Oversight and Outcomes, found that California is one of only two large states that make no attempt to screen drug and alcohol counselors.

"They don't do any criminal background checks," said John Hill, the author of the study. "They don't ask the counselors to report on their criminal histories. And as a result, people with serious criminal backgrounds can become counselors pretty easily -- including 23 registered sex offenders."

There are only seven organizations in California that register and certify counselors.

According to the report, one of the sex offenders was registered with the Breining Institute in Sacramento to work as a drug counselor. A year later, he pleaded guilty to felony drug possession.

Another counselor who registered with Breining, the report said, was arrested for driving under the influence and pleaded no contest to a reduced charge of reckless driving.

KCRA 3 found only a locked door at Breining's counseling office on Cottage Way in Sacramento, even though a sign in the window indicated it should be open on Mondays.

But the report raises overarching questions about a lack of oversight for drug and alcohol counseling in California.

"We found counselors who were revoked as drug and alcohol counselors who kept working," Hill told KCRA 3.

It said, "Breining Institute has been an advocate of criminal background checks for alcohol and drug counselors, as well as the maintenance of a centralized database for many years, and has been a principle supporter of several attempts to enact these changes through California legislation which have, so far far been rejected."

The report by the Senate Office of Oversight and Outcomes recommends the legislature put the state in charge of credentialing drug and alcohol counselors.